on my f650 twin, the stock cz525 & sprockets lasted 40,000km. in africa, with the scottoiler, i reckon a DID is gonna smoke that. i replaced the chain & sprockets with a DID & have done 25k since & they still look new, even though i am complacent with chain lube. i think you will know far far in advance if you need new sprockets. i'd rather carry a section of chain & fix a breakage. new chain is too heavy.

def bring tubes. i haven't seen any suitable here. even if you found an 18" tube (17" impossible) its gonna be too narrow.

the proper oil filters are worth bringing. i need a new one now & consensus on ADV is use the recommended because there are too many variables on spec.

i have serious doubts about slime in the tyres... too messy. you're not gonna have the water to clean this up on the side of the road.

i ran diesel oil in my f650 twin coz it was all i could find (and i had two gaping holes in the sump where 2.8 of 2.9L of 10w40 had leaked out). i think the whole oil debate is bullshit. if you're changing oil every 1500km i wouldn't stress the grade. just buy from a Total, Mobil (egypt) or shell/oil libya service station and she'll be right.

plugs, sure. i reckon on the f800 unless you are really shit in sand, the clutch kit isn't worth the space.

i wouldn't trust DHL to khartoum... my package is still lost somewhere in russia. for what its worth - spend a couple of days looking for parts locally. find the local bikers and ask them what is available. you will be surprised. i found electric submersible fuel pumps for my 650 twin in every big town i looked (khartoum, addis, tanga).

enjoy the trip.
d